Drag-saw.



No. 7l3,943. Patented Nov. [8, I902.

c. A. BENJAMIN;

DRAG SAW.

(Application filed Mm. 14, 1902.)

(No Model.)

m z-rsns c0, moroumouwunmnmu n c UNlTED STATES PATENT ()FFICE.

CHARLES A. BENJAMIN, OF MCPIIERSON, KANSAS.

DRAG-SAW.

SPEGIFIGATION forming part of Letters I'Patent N 0. 713,943, datedNovember 18, 1902.

Application filed March 14, 1902. Serial No. 98,218. (No model.)

To aZZ whom it may concern.-

Be it known that 1, CHARLES A. BENJAMIN, a citizen of the United States,residing at Mc- Pherson, in the county of McPherson and State of Kansas,have invented certain new and useful Improvements in Drag-Saws; and I dohereby declare the following to be a full, clear, and exact descriptionof the invention, such as willenable others skilled in the art to whichit appertains to make and use the same.

This invention has relation to the type of saws comprising a frame and asaw-blade held in the frame under tension and aims to pro- "ide a novelstraining mechanism for spreading the ends of the frame to subject thesawblade to the tension necessary for effective and efficient work.

The invention consists, essentially, of the novel features, details ofconstruction, and combinations of the parts, which hereinafter will bemore particularly set forth, illustrated, and finally claimed.

In the drawings hereto attached and forming a part of the specification,Figure 1 is a side view of a saw embodying the invention. Fig. 2 is adetail view of the joint between the sections of the frame, showing thetension device in section. Fig. 3 is a transverse section on the line XX of Fig. 2. Fig. L is a top view of the parts shown in Fig. 2. Fig. 5is a perspective view of an end portion of the saw-blade. Fig. 6. is asection on the line a a of Fig. 1.

Corresponding and like parts are referred to in the followingdescription and indicated in all the views of the drawings by the samereference characters.

The frame comprises similar sections 1 and 2, connected at their innerendsin such a way as to admit of spreading their outer terminals inorder to place the saw-blade 3 under tension. The frame may be of anydesired shape and construction, according to the particular use forwhich the saw is designed. The parts 1 and 2 may be formed either of baror tubular material, and in the case of drag-saws it is preferred toconstruct the frame of tubing. The saw-blade 3 is connected at its endsto the outer terminals of the frame by pins 4 or other selected meanscommonly employed for this purpose. For convenience of operation theframe is provided with an extension 5, constituting a handle and appliedin any convenient way.

In the preferable construction the inner ends of the sections 1 and 2are curved, as shown at 6 and 7, and are pivotally connected by thefastening S, passing through trans versely-aliniug openings in theoverlapped terminal portions. The extremities of the curved ends 6 and 7are oppositely beveled to form a \/-shaped space 9, in which is fitted awedge 10. A V-shaped space 11 is formed between the curved portions ofthe parts 6 and 7 and receives a wedge 12. These wedges 10 and 12cooperate to effect a turning of the sections 1 and 2 upon their pivotconnection 8, so as to spread the outer terminals of the parts 1 and 2,whereby the saw-blade 3 is strained or placed under tension. A link 13embraces the joint formed between the sections 1 and 2, and its sidemembers are slotted, as shown at 14:, to receive the ends of thepivot-fastening 8, which, in conjunction with the parts 10 and l2,holdthe link in place. The wedge 12 is preferably an integral part of thelink 13 and is the lower cross-bar thereof, the sides of its upperportion being oppositely inclined. to form the wedge. A setscrew 15 isthreaded into the upper cross-bar of the link, and its lower end isseated in a depression in the top side of the Wedge 10. The side bars ofthe link 13 closely embrace the sides of the joint, so as to preventlateral play of the sections 1 and 2, thereby holding them in line,which is essential to the effectiveness of the device when in use.

The size of the frame will depend upon the length of the saw-blade andthe special Work for which the saw is designed, and after the parts havebeen assembled and the saw-blade firmly attached to the outer ends ofthe frame the said blade is strained by turning the setscrew 15 so as toforce the wedges 10 and 12 into the spaces 9 and 11. A veryslightmovement of the set-screw 15 is sufficient to place the saw-bladeunder a high tension or to regulate the distance between the outerterminals of the frame to accommodate different lengths of saw bladeswithin certain limits. The

straining mechanism besides serving to adj nst the frame and maintainthe saw-blade under tension acts to strengthen and reinforce the jointand to hold the sections of the frame in alinement.

The pin lis made fast to the saw-blade and is concealed within thetubular frame and, projecting at its ends beyond the sides of the slotbin the frame in which the end of the sawblade is received, holds thesaid blade in place when under tension.

Having thus described the invention, what is claimed as new is 1. In asaw, a frame composed of sections, a wedge interposed between the endsof the sections, and means for moving the wedge to effect an adjustmentof the frame either to accommodate different lengths of saw-bladeswithin certain limits or to place the saw-blade under tension,substantially as set forth.

2. In a saw, a frame comprising pivoted sections, and a wedge interposedbetween the pivoted ends of the said sections to effect an outwardadjustment of the outer terminals of the said sections, substantially asand for the purpose set forth.

3. In a saw, a frame composed of sections pivotally connected at theirinner ends, a link fitted to the joint between the said sections, awedge held in place by the link, and means for forcing the wedge betweenthe pivoted parts of thejoint to effect a spreading of the outer ends ofthe aforesaid sections, substantially as specified.

4. In a saw, a frame comprising sections pivotally connected at theirinner ends, a link applied to the joint, wedges located at oppositesides of the pivot connection and supported by the link, and means forforcing the wedges together, whereby they cooperate to effect aspreading of the outer ends of the aforementioned sections,substantially as set forth.

5. In a saw, aframe com prising pivoted sections, having the extremitiesof the pivotal ends oppositely inclined, a Wedge, and means for forcingthe wedge into the angular space formed between the inclined extremitiesof the said pivotal ends to effect a spreading of the outer ends of theframe, substantially as and for the purpose specified.

6. In a saw, a frame comprising sections having their inner ends curvedand pivotally connected, and a wedge adapted to be forced into the spaceformed between the curved portions of the pivoted ends to efiect aspreading of the outer ends of the frame, substantially as specified.

7. In a saw, aframe comprising pivoted sections, a link embracing thejoint formed between the said sections, a wedge supported by said link,and means cooperating with the link to force the wedge between thepivoted parts of the joint to effect a spreading of the outer ends ofthe frame, substantially as set forth.

8. In a saw, a frame comprising sections having the inner ends curvedand overlapped, a pivot-fasteningconnecting the curved ends and havingits end portions extended, a link embracing the joint and having itsside portions slotted to receive the extended ends of thepivot-fastening, a wedge carried by the link, and means for forcing thewedge home to effect a spreading of the outer ends of the frame,substantially as set forth.

In testimony whereof I affix my signature in presence of two witnesses.

' CHARLES A. BENJAMIN.

Witnesses:

MARGUERITE CoMs, J OHN R. WRIGHT.

